STRAIT FLEX WF-100 4-Inch X 100-Feet Wide Flex 4 Paper Face Composite Tape X 100' WIDE-FLEX 4 PAPER-FACE COMPOSITE TAPE Ideal for hard-to-straighten vaults, butterfly vaults, hard-to-straighten outside corners & obtuse angles. Wide-Flex 400, a paper-faced, laminated composite corner tape from Strait-Flex